"It's not about what anybody else is going to do, it's about making myself better," Detwiler said. "I think competition's definitely healthy for anything you do. It's going to push you a little bit. Not to say if it wasn't a competition, anybody would get complacent, but I definitely think competition is going to push everybody, make everybody better."
The Nationals have starting-pitching depth, with the likes of Tanner Roark and Taylor Jordan also options as the fifth starter. Washington also has made little secret of its desire to add at least one left-handed reliever, and Detwiler could be an option if Rizzo can't fill the need through free agency or the trade market.
Detwiler, who turns 28 in March, has made 16 of his 85 career appearances out of the bullpen and posted a 1.11 ERA across 32 1/3 innings. Last season, when he made 13 starts, was the first time in Detwiler's career he didn't appear as a reliever.
"I wouldn't necessarily say I'd be OK with it," Detwiler said of returning to the bullpen. "It's not my job to tell them, 'No, I'm this,' or 'No, I'm that.' They're the ones telling me what to do. It's one of those things where I know I can do it. I've proved I can do it in the past. Whether that helps or hurts me right now, who knows?
"But like I said, if I go into Spring Training -- and I'm going in as a starter -- and I don't do well, then yeah, there's a very good possibility that's going to happen. But if I go in there and throw like I have in the past and throw like I know I can, then I don't think there's going to be any problems."
The biggest issue for Detwiler might be health. He suffered a strained oblique and a herniated disk in his back last season, served two stints on the disabled list and didn't pitch after July 3. Detwiler tried to come back, but after each time he threw, his back would "lock up" the next day, to the point where he could barely move. A season that began with a 2.53 ERA through seven starts had turned sour.
Although Detwiler's rehab didn't progress quickly enough to allow him to return to the Nationals late last season, he did pitch in the instructional league this fall. He made four starts there, his last spanning six innings and about 80 pitches and causing no ill effects. That gave Detwiler "peace of mind" heading into the offseason.
Nats strength-and-conditioning coaches John Philbin and Matt Eiden mapped out a rehab plan for Detwiler, with exercises to help stabilize his back and core. That's now part of his offseason workout plan.
"I feel I'm going to come back stronger than I ever have been, because I'm doing all these extra exercises now," Detwiler said. "I think it definitely shows me how much your back and your core really affects everything you do in pitching."